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<h1>交替风格</h1>

<h3>问题:</h3>

<p>你想通过数据集合动态的生成交替背景色的列表.</p>

<h3>方法:</h3>

<p>Give templetor access to the <code>int</code> built-in and use modulo to test.</p>

<h2>code.py</h2>

<pre><code>web.template.Template.globals['int'] = int
</code></pre>

<h2>template.html</h2>

<pre><code>&lt;ul&gt;
$var i: 0
$for track in tracks:
    $var i: ${int(self.i) + 1}
    &lt;li class="
    $if int(self.i) % 2:
        odd
    $else:
        even
    "&gt;$track.title&lt;/li&gt;
&lt;/ul&gt;
</code></pre>

<h2>New Templetor</h2>

<p>In the new implementation of templetor (which will be the default when version .3 is released), within any template loop you have access to a $loop variable.  This works like so:</p>

<pre><code>&lt;ul&gt;
$for foo in foos:
    &lt;li class="$loop.parity"&gt;
    $foo
    &lt;/li&gt;
&lt;/ul&gt;
</code></pre>

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    <p>started by <a style="color: gray;" href="http://www.aaronsw.com/">Aaron Swartz</a> (<a style="color: black;" href="mailto:webpy@aaronsw.com">webpy@aaronsw.com</a>)</p>

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